// Numbas version: exam_results_page_options
{"name": "SP Error bars true or false (5)", "extensions": [], "custom_part_types": [], "resources": [["question-resources/error_bars.png", "/srv/numbas/media/question-resources/error_bars.png"], ["question-resources/error_barsv2_886.png", "/srv/numbas/media/question-resources/error_barsv2_886.png"]], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "SP Error bars true or false (5)", "tags": ["LANTITE"], "metadata": {"description": "<p>Used for LANTITE preparation (Australia). SP = Statistics &amp; Probability strand. Students are shown&nbsp;a bar chart with error bars&nbsp;and asked one of five possible questions.</p>", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "statement": "<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<p>A researcher wanted to examine the relationship between caffeine intake and short-term memory. He designed a memory test for 40 participants. The participants&nbsp;were all instructed to avoid consuming&nbsp;caffeine that day before attending the memory test experiment.</p>\n<p>Half of the participants were asked to drink a caffeine drink immediately prior to the commencement of the experiment. The other half were not. All participants were then given an identical list of eighteen random three-digit numbers and asked to memorise them in order.</p>\n<p>They were given one minute initially to memorise the numbers, then they were tested. The same list of&nbsp;three-digit numbers was returned to the participants after the test for another minute&nbsp;of study. They were then each tested again. This process was repeated until the participants had been tested five times, with access to the list of numbers for one minute in between each test.</p>\n<p>The mean and standard deviation for the number of correctly recalled numbers was calculated for each group for each test attempt. The results are shown in the chart below. The error bars represent the standard deviation.</p>\n<p><img src=\"resources/question-resources/error_barsv2_886.png\"/></p>\n<p></p>", "advice": "<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<p>{advicetext}</p>\n<p></p>", "rulesets": {}, "extensions": [], "variables": {"Scenarios": {"name": "Scenarios", "group": "Ungrouped variables", "definition": "json_decode(safe(\"[{\\\"question\\\":\\\"Between the two groups, there was less variation within the Caffeine group compared to the No-Caffeine group.\\\",\\n  \\\"answer\\\":\\\"true\\\",\\n  \\\"distractor1\\\":\\\"false\\\",\\n  \\\"distractor2\\\":\\\"it is not possible to say based on the information given\\\",\\n  \\\"advice\\\":\\\"If asked about variation within a group, look at the black lines (error bars), as they show the standard deviation either side of the mean, of each group at each point in time. The standard deviation is a measure of spread or variability within the group. The error bars are consistently shorter for the orange (Caffeine) bars than for the corresponding grey (No Caffeine) bars, so the statement is true.\\\"\\n  },\\n  \\n  {\\\"question\\\":\\\"The error bars for the two groups overlapped at two points in time.\\\",\\n   \\\"answer\\\":\\\"false\\\",\\n   \\\"distractor1\\\":\\\"true\\\",\\n  \\\"distractor2\\\":\\\"it is not possible to say based on the information given\\\",\\n  \\\"advice\\\":\\\"If two error bars overlap, part of one bar will be directly underneath the other bar, for the same points in time. The only time this occurs is for the first test attempt. Therefore the statement is false.\\\"\\n  },\\n  \\n  {\\\"question\\\":\\\"There was less variation within the No-Caffeine group as time went on.\\\",\\n   \\\"answer\\\":\\\"false\\\",\\n   \\\"distractor1\\\":\\\"true\\\",\\n  \\\"distractor2\\\":\\\"it is not possible to say based on the information given\\\",\\n  \\\"advice\\\":\\\"If asked about variation within a group, look at the black lines (error bars), as they show the standard deviation either side of the mean, of each group at each point in time. The standard deviation is a measure of spread or variability within the group. The error bars for the No-Caffeine (grey) bars become longer at each test attempt. Therefore the statement is false.\\\"\\n  },\\n  \\n  {\\\"question\\\":\\\"Both groups improved the most between the first and third attempts.\\\",\\n   \\\"answer\\\":\\\"true\\\",\\n   \\\"distractor1\\\":\\\"false\\\",\\n  \\\"distractor2\\\":\\\"it is not possible to say based on the information given\\\",\\n  \\\"advice\\\":\\\"The No-Caffeine (grey) group recalled an average of two additional numbers at the second test attempt, two more in the third test attempt, then one, then none. The Caffeine (orange) group recalled an average of three additional numbers at the second test attempt, three more at the third test attempt, then one, then one. Therefore the statement is true.\\\"\\n  },\\n  \\n  {\\\"question\\\":\\\"Overall, the Caffeine group performed better in the experiment.\\\",\\n   \\\"answer\\\":\\\"true\\\",\\n   \\\"distractor1\\\":\\\"false\\\",\\n  \\\"distractor2\\\":\\\"it is not possible to say based on the information given\\\",\\n  \\\"advice\\\":\\\"If asked about overall performance, look at the coloured bars, as they show the average performance of each group at each point in time. At each test attempt, the orange (Caffeine) bar is longer than the grey (No-Caffeine) bar, therefore the statement is true.\\\"\\n  }\\n]\"))", "description": "<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<p>A listing of all four possible questions with correct answer, distractors and Advice.</p>", "templateType": "json"}, "answer": {"name": "answer", "group": "Ungrouped variables", "definition": "scenario[\"answer\"]", "description": "<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\">The particular question that will be asked.The particular question that will be asked.</div>\n<p>The correct answer to the particular question.</p>", "templateType": "anything"}, "distractor1": {"name": "distractor1", "group": "Ungrouped variables", "definition": "scenario[\"distractor1\"]", "description": "<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<p>The first incorrect answer for the question.</p>", "templateType": "anything"}, "distractor2": {"name": "distractor2", "group": "Ungrouped variables", "definition": "scenario[\"distractor2\"]", "description": "<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<p>The second incorrect answer for the selected question.</p>", "templateType": "anything"}, "scenario": {"name": "scenario", "group": "Ungrouped variables", "definition": "random(scenarios)", "description": "<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<p>Randomly select one of the four scenarios (question, answer, distractors and Advice).</p>", "templateType": "anything"}, "question": {"name": "question", "group": "Ungrouped variables", "definition": "scenario[\"question\"]", "description": "<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<p>The particular question that will be asked.</p>", "templateType": "anything"}, "advicetext": {"name": "advicetext", "group": "Ungrouped variables", "definition": "scenario[\"advice\"]", "description": "<p>The Advice text specific to the&nbsp;particular&nbsp;question.</p>", "templateType": "anything"}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["Scenarios", "scenario", "question", "answer", "distractor1", "distractor2", "advicetext"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "1_n_2", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n<p>Select the correct response to the following statement regarding the chart above:</p>\n<p>{question}</p>", "minMarks": 0, "maxMarks": 0, "shuffleChoices": true, "displayType": "radiogroup", "displayColumns": 0, "showCellAnswerState": true, "choices": ["<div id=\"MathJax_Message\" style=\"display: none;\"></div>\n{answer}", "{distractor1}", "{distractor2}"], "matrix": ["1", 0, 0], "distractors": ["Well done!", "Read the information above the chart carefully, then look at the chart again.", "Read the information above the chart carefully, then look at the chart again."]}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "contributors": [{"name": "Adelle Colbourn", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2083/"}]}]}], "contributors": [{"name": "Adelle Colbourn", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2083/"}]}